1. Field of the Invention
The present invention relates to a drawing apparatus, and a method of manufacturing an article.
2. Description of the Related Art
As one of apparatuses used in the manufacturing step (lithography step) of semiconductor devices and the like, a drawing apparatus for drawing a pattern on a substrate using charged particle beams is known. As the design rules of semiconductor devices become finer recently, a high drawing accuracy is required for such a drawing apparatus. To meet this requirement, it is important to accurately measure the relative positions between a substrate stage that holds a substrate and charged particle beams that irradiate the substrate.
Japanese Patent Laid-Open. No. 2005-347054 describes a drawing apparatus in which a detector configured to detect a charged particle beam is provided on a substrate stage that holds a substrate. In the drawing apparatus described in Japanese Patent Laid-Open No. 2005-347054, a charged particle beam is detected by the detector while moving the substrate stage, thereby measuring the relative positions between a plurality of charged particle beats and the substrate stage.
In the drawing apparatus described in Japanese Patent Laid-Open No. 2005-347054, the detector that detects a charged particle beam is provided on the substrate stage. The detector generates heat when irradiated with charged particle beams. When the heat is transmitted to the substrate stage, the substrate stage may deform due to the heat. As a result, it may he impossible to make a charged particle beam correctly strike a target position on the substrate held by the substrate stage.